The visitor center is open every day except Thanksgiving, Christmas, and New Years Day. Summer hours are May 15 through September 30. The visitor center features a large diorama of Miocene mammal fossils, 12-minute park movie, and the James H. Cook Collection of Lakota artifacts, a unique collection of American Indian artifacts gifted to the Cook family by Chief Red Cloud and his descendants. Two trails are open every day from dawn till dusk.